No log on promt, just blue screen at start up.

My iMac suddely started to show grey bubbles at start up, but Safe start still worked. I then reinstalled the OS and now it just show a blue screen instead of the log on window. I've checked the log files and the system log file says something about ASIC Hang log. Could it be the video card that causes this. I've checked the HD - it looks OK and the computer can be started with Safe start.

2 Answers

If you see a blank blue screen, or a blue screen with a progress indicator (looks like a colored pinwheel), you may have an incompatible login item.

To find out if you have an incompatible login item:

Shut down your computer and wait 30 seconds.

Press the power button.

Immediately after you hear the startup tone, press and hold the Shift key.

Release the Shift key when you see the gray Apple and progress indicator.

Choose Apple menu > System Preferences.

Click Accounts, then click Login Items.

Make a list of the login items--you'll need to remember them later.

Select all of the login items and click Remove.

Choose Apple menu > Restart.

If this solves the problem, open Accounts preferences again and add the login items one at a time, restarting your computer after adding each one, until the symptom occurs again. (You can start up your computer normally when you're adding the login items.) When you've found the incompatible login item, use the procedure above to remove just the problem item.

YES -- this could be a hardware issue with the Graphics Card / Logic Board.

Since it starts in "safe" mode, and if you look at the files in System/Library/Extensions after a safe boot you will notice that they are not the same as those in a "normal boot'... there could be a corrupt or unneeded driver in the normal set that you could delete or replace. I have had success doing that with a troublesome machine in the past.

Good Luck,

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